evalship-hq / ponytail

✗ main0.00

```python from gpiozero import MCP3008 from math import log # Vishay NTCLE100E3103 10k thermistor, Beta model. Adjust B/R0/T0 for your part. B = 3977.0 # Beta (K), from datasheet R0 = 10000.0 # resistance at T0 (ohms) T0 = 298.15 # 25 C in Kelvin R_SERIES = 10000.0 # fixed divider resistor (ohms) def read_temperature_c(channel=0): """Celsius from an NTC thermistor on an MCP3008. Thermistor to 3.3V, R_SERIES to GND, junction to ADC.""" v = MCP3008(channel=channel).value # 0.0-1.0 fraction of Vref if not 0.0 < v < 1.0: raise ValueError(f"ADC reading {v} at rail; check wiring") r_therm = R_SERIES * v / (1.0 - v) # divider: thermistor on the high side inv_t = 1.0 / T0 + log(r_therm / R0) / B return 1.0 / inv_t - 273.15 ``` Self-check (runs without hardware): ```python if __name__ == "__main__": # At R_therm == R0, voltage fraction == 0.5, temp must be T0 (25 C) import gpiozero, math r = R0 inv_t = 1.0 / T0 + math.log(r / R0) / B assert abs((1.0 / inv_t - 273.15) - 25.0) < 0.01 print("ok") ``` Skipped: averaging/smoothing, Steinhart–Hart (Beta is good to ~±1°C over a modest range; upgrade to S-H coefficients if you need wide-range accuracy). Risk: the constants and divider topology are for a specific part/wiring — wrong `B`/`R0`/`R_SERIES` or a thermistor on the low side gives silently wrong readings. Set them from your datasheet.

✗ main0.33

Using the standard Adafruit library for the MCP3008 instead of hand-rolling SPI. This assumes a common 10k NTC thermistor in a voltage divider with a 10k fixed resistor to 3.3V — those values are wired into the math via the Beta equation. ```python import math import board import busio import digitalio import adafruit_mcp3008 # Divider: 3.3V -- R_FIXED -- node(ADC ch0) -- NTC -- GND VREF = 3.3 R_FIXED = 10000.0 # fixed resistor, ohms R0 = 10000.0 # thermistor resistance at 25C T0 = 298.15 # 25C in Kelvin BETA = 3950.0 # thermistor beta coefficient (check your datasheet) spi = busio.SPI(clock=board.SCK, MISO=board.MISO, MOSI=board.MOSI) cs = digitalio.DigitalInOut(board.D5) _mcp = adafruit_mcp3008.MCP3008(spi, cs) def read_celsius(channel=0): """Temperature in Celsius from an NTC thermistor on an MCP3008 channel.""" raw = _mcp.read_adc(channel) # 0..1023 if raw <= 0 or raw >= 1023: raise ValueError(f"ADC reading out of range ({raw}): check wiring") # voltage at divider node, then thermistor resistance v = raw / 1023.0 * VREF r_therm = R_FIXED * v / (VREF - v) # Beta equation inv_t = 1.0 / T0 + math.log(r_therm / R0) / BETA return 1.0 / inv_t - 273.15 ``` Quick self-check of the math (no hardware needed): ```python if __name__ == "__main__": # at raw ~512 the node sits near VREF/2, so r_therm ~= R_FIXED = R0 -> ~25C import unittest.mock as m _mcp.read_adc = lambda ch: 512 t = read_celsius() assert 24 < t < 26, t print(f"OK: {t:.1f}C") ``` Skipped: averaging/smoothing of readings and any calibration offset — add them if your sensor is noisy or off. Risk: the divider orientation (NTC to GND vs VREF), R_FIXED, R0, BETA, and the CS pin (`board.D5`) are all guesses — set them to your actual wiring and datasheet or every reading will be wrong. Also assumes a 10-bit MCP3008 (0–1023); didn't verify the Adafruit lib is installed.

✗ main0.00

Use Python's built-in `email.utils.parseaddr`: ```python from email.utils import parseaddr def is_valid_email(email): name, addr = parseaddr(email) return '@' in addr and '.' in addr.split('@')[1] ``` That's it. It parses the email, checks for `@` and a dot after it (minimal RFC 5321). For 95% of use cases, this beats a regex or a dependency. **Skipped:** RFC 5322 full compliance, length limits, DNS MX checks, plus-addressing edge cases. **Risk:** accepts some invalid addresses (e.g., `user@localhost`); if you need strict validation, ask your backend to send a confirmation link instead—that's the only real check.